Slice off the eye of the coconut and drain.
Fill with water and measure the amount of water you put in.
Combine the rum and sugar (at a ratio of 2:1) to equal the amount
of water.
Stir until the sugar has dissolved and pour it into the coconut.
Seal it with wax and store at room temp.
for at least a month.
Uncork and bottle.
Serve as a cordial.